1. Technical Field
The present invention relates to a radio-frequency heating apparatus and a radio-frequency heating method for heating an object placed in a heating chamber.
2. Background Art
Conventionally, in order to improve heating efficiency and eliminate uneven heating and provide uniform heating for a radio-frequency heating apparatus which heats an object such as food using radio-frequency power, various techniques have been disclosed for providing local heating based on the state and geometry of the object, and for stirring radiated radio-frequency power in a heating chamber.
For example, Patent Literature 1 discloses a microwave oven which has a radiation antenna on the outer periphery of an emission antenna. In the microwave oven, by rotating an emission antenna, a state in which the emission antenna is radio-frequency coupled with the radiation antenna, and a state in which the emission antenna is not radio-frequency coupled with the radiation antenna are controlled, and apparent size of the antenna is changed so that a state in which microwave is supplied to a small region in a concentrated manner, and a state in which microwave is uniformly distributed are controlled.
In addition, Patent Literature 2 discloses a microwave oven which is provided with a plurality of rotation antennas and a unit to detect a temperature distribution of an object. This microwave oven detects the temperature distribution of the object, and determines a portion of the object to be heated based on the detected temperature distribution information, and rotates a rotation antenna accordingly to control the directivity of the antenna.
In addition, Patent Literature 3 discloses a microwave oven which is provided with a plurality of flat antennas, and varies the phase of the microwave to be supplied to the flat antennas, then changes the directivity of the microwave radiated from the flat antennas, thereby stirring the microwave without using a stirrer.